Shock absorber

Abstract

The present invention provides a modified shock absorber, which comprises a shock damping tube, an upper spring seat, a lower spring seat, a fixing ring, a resilient part, and a bearing seat. The resilient part comprises two springs of different spring constants. The bearing seat is used to connect the two springs up and down in series. Because the spring of larger spring constant restores to its original state more easily, and the spring of smaller spring constant absorbs energy more easily, higher effect of stability can be provided when they are connected in series. In other words, two springs of different spring constants connected in series are exploited to absorb energy in two steps so that a car will not easily skid and will have better stability when making a turn.

What is claimed is:  
     
         1 . A shock absorber for a car, comprising: 
 a shock damping tube;    an upper spring seat and a lower spring seat positioned on said shock damping tube; and    compound resilient means surrounding the outer periphery of said shock damping tube abutting said upper spring seat and said lower spring seat.    
     
     
         2 . The shock absorber according to  claim 1  wherein the periphery of said shock damping tube has a plurality of threads, and said lower spring seat is threaded on to said shock damping tube.  
     
     
         3 . The shock absorber according to  claim 1  wherein the inside of said shock damping tube includes a mobile rod protruding out of and moving relative to said shock damping tube, and a bushing is provided to mate with said mobile rod.  
     
     
         4 . The shock absorber according to  claim 1  wherein the periphery of said shock damping tube has a fixing ring.  
     
     
         5 . The shock absorber according to  claim 1  wherein said compound resilient means comprises a primary spring having a relatively large spring constant and a secondary spring having a relatively small spring constant, with said primary spring abutting between said bearing seat and said lower spring seat, and said secondary spring abutting between said bearing seat and said upper spring seat.  
     
     
         6 . A shock absorber: 
 a shock damping tube;    an upper spring seat and a lower spring seat positioned on said shock damping tube; and    a first spring having a first spring constant and a second spring having a second spring constant, said first and second springs being coupled together in series by a bearing seat and arranged in surrounding relation to the outer periphery of said shock damping tube and abutting said upper spring seat and said lower spring seat.    
     
     
         7 . The shock absorber according to  claim 6  wherein the periphery of said shock damping tube has a plurality of threads, and said lower spring seat is threaded on to said shock damping tube.  
     
     
         8 . The shock absorber according to  claim 6  wherein the inside of said shock damping tube includes a mobile rod protruding out of and moving relative to said shock damping tube, and a bushing is provided to mate with said mobile rod.  
     
     
         9 . The shock absorber according to  claim 6  wherein the periphery of said shock damping tube has a fixing ring.  
     
     
         10 . The shock absorber according to  claim 6  wherein said first spring comprises a relatively large spring constant and said second spring comprises a relatively small spring constant, with said first spring abutting between said bearing seat and said lower spring seat, and said second spring abutting between said bearing seat and said upper spring seat.